As shown in FIGS. 11 and 12, a plane pulse motor comprises a stator 10 having a number of magnetic pieces 100 that are formed by dividing a planar surface of a magnetic substance by orthogonal grooves into a lattice form having a suitable pitch, and also a movable member (armature) 20 comprising two perpendicularly arranged magnetic pole members 103. Each of the magnetic pole members 103 comprises a plurality of magnetic pieces 101, 102 formed out of permanent magnets, each having a plurality of magnetic pole legs with a pitch deviating from the pitch of the lattice of the stator 10 by a half pitch. By the attracting force of the magnetic pole members 103, the movable member 20 of the plane pulse motor is held on the surface of the stator 10, and by controlling exciting coils 104 wound around the magnetic pieces 101 and 102, the movable member 20 is shifted in an arbitrary direction along the surface of the stator 10. For smoothing the movement of the movable member 20 along the surface of the stator 10, air is injected between the member 20 and the stator 10 as shown by an arrow mark A so as to form an air layer.
It is apparent that the stator 10 with the movable member 20 attracted thereon, may be placed not only on the floor, but also on either the side walls or ceiling of a structure.
Because of the above described construction, the plane pulse motor has been heretofore used in combination with a manipulator with a required tool secured to an output shaft of the manipulator for implanting, for instance, electronic parts on a printed circuit board.
In the case of actual application, however, besides the aforementioned arbitrary movement of the movable member 20 along the surface of the stator 10, further degrees of freedom, such as movements around and along the output shaft 105 of the movable member 20, are required. Accordingly, it becomes necessary to mount a separate actuator such as a robot 106 having a rotatable arm as shown in FIG. 10 instead of the output shaft 105 of the movable member 20. However, in a case where a moment M of a falling direction is applied to the movable member 20 as a result of the provision of the separate actuator, the moment M must be restricted in a range not exceeding the moment-withstanding capability of the attracting force applied to the movable member 20, and furthermore, there arise problems such as increasing weight because of the actuator, increasing the size of the movable member 20, and complicating the control of the same.
The object of the present invention is to provide a manipulator using a plane pulse motor wherein the above described problems of the conventional arrangement are eliminated, the construction is simplified and the size is reduced regardless of the provision of a plurality of movable members, while the operation thereof is stabilized, and the degree of freedom of the movement is increased.